Post-Chemo Cognitive Complaints Tied to Brain Activity Changes

(HealthDay News) — For patients undergoing chemotherapy for breast cancer, cognitive complaints after treatment may be associated with changes in brain activity, according to a study published online May 27 in the Journal of Clinical Oncology.

Sabine Deprez, PhD, from the Katholieke Universiteit Leuven in Belgium, and colleagues assessed whether cognitive complaints after breast cancer treatment correlate with detectable changes in brain activity during multitasking. A functional magnetic resonance imaging multitasking task was performed in the scanner by 18 patients before the start of chemotherapy treatment (t1) and 4–6 months after completing treatment (t2). The same task was performed at matched intervals by 16 patients who were not scheduled to receive chemotherapy and 17 matched healthy controls.

The researchers found that, in chemotherapy-treated patients, voxel-based paired t tests revealed significantly decreased activation from t1 to t2 in the multitasking network, but no changes were observed in the control groups. No differences were seen between the groups at baseline. The chemotherapy-treated patients, but not controls, reported a significant increase in cognitive complaints at t2. There were significant associations between these increases and the decrease in multitasking-linked brain activation. There was a significant group-by-time interaction, with chemotherapy-treated patients, but not healthy controls, showing decreased activation.

"These results suggest that changes in brain activity may underlie chemotherapy-induced cognitive complaints," the authors write. "To the best of our knowledge, this is the first longitudinal study providing evidence for a relationship between longitudinal changes in cognitive complaints and changes in brain activation after chemotherapy."